A. Field of the Invention
The present invention relates to a new and improved method for fabricating ports in a fuel burner wherein the ports are fabricated in a single movement of the tool relative to the burner.
B. Description of the Prior Art
Presently, many different methods of fabricating ports in a sheet metal fuel burner are available. However, these methods require a multiplicity of steps and movements to fabricate or cut the ports in a complete burner body, particularly if the burner body is of a complex configuration; for example, and H-shaped configuration useful in gas fired barbecue cookers.
Of the different procedures followed, some employ drilling of the various ports in the burner body. Drilled ports in thin sheet metal vary from a true round hole and have an irregular burr or finn carried forward by the drill which results in uneven burning and ragged flames. Moreover, such a process is expensive and requires a plurality of steps or separate manufacturing operations for fabricating several ports, particularly in a complex configuration.
Another method utilizes a mandril and a punch such as that illustrated in U.S. Pat. No. 3,386,431. This patent also discloses the use of a roller or punch wheel; however, this method has the disadvantage that an elaborate operation is necessary for fabricating ports in a burner having a complex configuration.